Bikram yoga's benefits might have nothing to do with the heat

Until recently, we mostly relied on ancient knowledge passed down through teachers to tell us how and why yoga is good for the body. But with all the various claims different types of yoga make about health benefits, it’s also good to know that the scientific community is trying to do a bit of fact checking. A new study has determined that while Bikram yoga (which is done in a heated room) is beneficial to cardiovascular health, its signature high studio temperatures might not be as necessary as previously thought.

“It’s still a very new area of research, and there are still relatively few studies on hot yoga in comparison to other styles of yoga,” Stacy D. Hunter, assistant professor in the department of health and human performance at Texas State University, tells Yahoo Lifestyle. So far, Hunter says, research has shown that Bikram has benefits for mental health, reductions in cholesterol, fasting insulin, flexibility, arterial health, and endothelial function (which relates to the dilation of arteries in response to blood flow). “But what we didn’t know was whether or not the heated environment was playing a role.”

Hunter is one of the authors of the study, published in the journal Experimental Physiology, which tested 80 adults between the ages of 40 and 60 over the course of 12 weeks. One group practiced Bikram yoga in a hot studio (about 105°F) for 90 minutes, three times a week. Another group practiced Bikram at the same frequency but in a studio that was about 73°F, and a third group did not alter their physical activity.

The researchers thought that those in the hot group would see more improvement to their blood and lymphatic cells than the practitioners of yoga in a neutral-temperature studio. After all, studies have shown that using a sauna regularly has those benefits, reducing the risk of heart disease. But after the 12 weeks, both yoga groups showed the same level of improved endothelial function, a significant difference from the control group.

The one difference between the temperature groups was that the hot yogis’ body fat percentages went down. Otherwise, it appears that the movements of Bikram, not the studio temperature, are what makes the practice good for the arteries.

“I don’t think the study is showing that people shouldn’t do it,” says Hunter, who is herself a practitioner of Bikram. “I also think there’s evidence to support the fact that the 105-degree studio isn’t necessary for some of the potential benefits of the practice.”

What does account for the way the Bikram practice improved endothelial function? Hunter has one untested theory. “This is just speculation here, but I do think there are benefits to the isometric components of the postures,” she said. “Isometric muscular contractions — in which you’re getting into that posture, your muscles are generating tension, but you’re holding not shortening or lengthening — have been shown to improve endothelial function as well.”

Hunter, who is also the research and education director of the yoga research nonprofit Pure Action, plans to shift her focus to study how yoga practices will help people in a clinical setting who suffer from problems such as hypertension or arthritis.

With the release of these findings, Hunter says she understands that Bikram teachers and studio owners are going to feel protective of their practice’s philosophy.

“I’m hoping that people will at least read the article and try to understand that whether research depicts it in a positive, negative, or neutral light, it’s still knowledge gained about the practice,” she says.